Aerially-propelled speed boat



Patented Oct. 2, 1928.

UNITED STATES HENRY LOWE BROWNBAGK, or NORRISTOWN, PENNSYLVANIA, AssreNon 'ro new- BACK MOTOR LABORATORIES, INC., OF

YORK. i

NEW YORK, N. Y., A CORPORATION OF NEW mamnirsraornnrnn srnn'n BOAT.

Application ma July 21, 1925. Serial No. 45,023.

This invention relates to aerially propelled speed boats, and the rincipal object of the invention is to provi e a speed motor boat driven by an aerial propeller which boat,

upon attaining sufiic-ient speed, will be supported on the surface of the water through dynamic reaction upon its bottom surface,

' the hull of the boat and the aerial propeller being so arranged that the center of lift of the bottom surface of the hull, and the center of resistance of the hull is forward and below the center of gravity of the boat, and that the center of thrust of the aerial propeller is above and to the rear of the center of gravity, so that any derangement of the balance of forces sustaining, retarding and propelling ,the boat.

will tend to raise the boat at the center of gravity, and any substantial increase in the application of propelling power or any comb nation of external forces which may tend to raise the stern or depress the bow sud .denly will tend to move the center of lift and the center of resistance forward, the center of gravity being of course stationary, and thereby restore the stability of the hull, or these remaining stationary, to revolve the boat about the resultant force, thus attempting to lift the boat at its center of gravity and depressing the bow, moving the center of resistance forward and restoring the'equilibrium offorces acting on the hull.

I- will explainthe invention with reference tothe accompanying drawing which illustrates one practical embodiment thereof to enable those familiar withthe artto adopt and use the same, and will summarize 1n the claims the essentials of the invention, the

f novel features ofconstructiomand'the novel 40 combinations of parts for all of "which protection is desired. A

In the drawings Fig. 1 illustrates diagrammatically, any

preferred ,form of the invention. ,v Figs; 2 and 3 illustrate modifications of thehull of the'boahv.

- The drawing diagrammatically illustrates aerially propelled d boats embodying my invention. The ull A of the boat maybe of any desired form, such as the ordinary inted nose ty e, or the sea-sled type, the ength thereof preferably short relative to the width thereof. The boat may be cabin A above the deck lot the .hull, is a motor A of any desired type, and of sulficient power to propel the hull. at proper speeds, the shaft of the motor A extending to the rear of the cabin and having an aerial propeller A of suitable design and size fixedly mounted thereon.

The bottom surface of the hull A in Fig. 1 1s stepped as at A, the deeper portion of the hull A be ng forward of the stepped portion A. The bottom' surface of the hull, both fore and aft of the stepped portion A, is substantially flat, but may be slightly'vs shaped, or rounded, and V-shaped at the bow to prevent pounding with the forward end of the bottom surface sloping upwardly as a at A in the usual manner in order that the beat will more readily ride upon the surface of the water as the; speed increases. .A suitable rudder (not shown) operating in either air or water, may be provldedfor steering the boat. i

As shown in Fig. 2, the bottom surface of the hull is provided with planing or reaction surfaces designed to presentsuitable angles to'the plane of the water to provide the desired reactions, instead of b stefi ped as in Fig. 1. 1 ig. 3; illustrates my invention applied 'to eing v a tandem hull in which the resultant cen-' ters of lift, gravity, resistance and thrustwould be located approximatelyas in Figs. 1 and'2,.the after section of the .hull being of less-depth than the forward section. 4

Other types of hulls may be used, and j preferably the bow end of the bottom; sur-" face of each-type ofhull is slightly \l-shapech forward of the propeller A andcoaxial with theshaft of motor A said center of thrust 0 being disposed considerably-above and to the rear of the center of gravity B. The.

center of lift.

center of resistance of the hull A would be located approximately as indicated at D in the drawings, and the center of lift would be located as indicated at E, said center of By the above design the boat propelled by the aerial propeller A upon obtaining sultcient speed will be supported on the surface.

ofthe water through dynamic reaction upon its bottom surface and any substantial increase in the application of propelling power or any application of external forces tending to suddenly elevate the sterncor depress the bow of the boat will tend to move the center of lift and the center of resistance forward and to raise the boat at the center of gravity, the portion of the bottom surface of the boat forward of the stepped portion A or the portion designed'for the major dynamic reaction touching the surface of the water.. The portion of the bottom surface of the boat to the rear of the stepped portion A orthe portion designed for the ma jor dynamic reaction will run on the surface of the water and the boat will act substantially like a hydroplane skimming the surface of the water, since the center of thrust C isabove and tothe rear of the center of gravity.

By the above arrangement wherein the center of lift E of the bottom surface, and the center .of resistance D of the hull is forward of and-below the center of gravity B of the boat, and the center of thrust C is above and to the rear of the center of gravity B any derangement of the balance of forces sustaining, retaining, and propelling the boat will tend to raise the boat at its center of gravity and move the center of lift E forward, thereby restoring the balance of forces, and hence tending to restore thesta- "bility of the 111111.

As shown by the arrows in the drawing,

the forces C and D tendto revolve the boat in an anti-clockwise direction around B as a center. This tendency is opposed by the forces E and B which tend to revolve the boat in a clockwise direction around D as a center.- An force tending to destroy the e uili'brium o the resultant of the moments 0 these unbalanced forces will be opposed by an opposite force which will-close the diagram 0 forces, and maintain equilibrium. Thus also, a sudden shutting off of power will tendto shift the center, of resistance q back, raising the bow, and automatically in- I creasingthe-resistance of the hull, givlng a powerful brakingefiect. I do not limit my invention to the exactform shown in-the drawing, for. obviously of the hull. the center of resistance being disposed forward of the center of gravity,

and the center of lift being disposed forward of the center of resistance; and means above the center of gravity for propelling the boat, the center of thrust thereof being disposed above-andvin rear of the center of gravity; whereby any change in the propelling thrust will shift the centers of. lift and resistance to maintain a. balance of forces during acceleration; and whereby the rear portion of the bottom of the hull will skim the surface of the water when at speed.

2. A boat of the character specified comprising a hull so designed that its center of gravity is disposed in rear of the-mid-section of the hull, the center of resistance being disposed below and forward of the center of gravity, and the center of lift being disposed forward of the centerof gravity, and the center of lift being disposed forward of the center of resistance; and anair propeller at the rear of the hull for propelling the boat, the center of thrust thereof being disposed above and in rear ofthe center of gravity; whereby any increase in the propelling thrust will shift the centers of lift and resistance forward to maintain a balance of forces during acceleration; and whereby the rear. portion of the bottom of the hull will skim the surface of the water center of gravity is disposed in rear of the mid-section of the hull, the center of re- 5 sistance being disposed below and in front of the center of gravityand in rear of the step in the reaction surface, and the center of lift being' disposed forward of the center of resistance and substantially at the step in the reaction surface; and means above the center of gravity for propelling the boat, the center of thrust thereof being disposed above and in rear of the center. of grav1ty; whereby any increase in the propell ng thrust will tend to shift the centers of lift and resistance forward to maintain a balance of forces during acceleration, and

whereby the bottom of the hull in rear of 'step will skim the surface of thevwater whenv at speed; -4

4, Aboat of the character specified comprising a hull having a stepped reaction'sur face, said hull being so designed that its a:

center-of gravity ,is disposed in rear ofithe midseetlon of; the hul1,'.the center of .reslstance being d sposed below and in front of gravity, and the gravity and lift forces neaasee a face; and an air propeller at the. rear of the hull for propelling the boat, the center of thrust thereof being disposed above and in rear ofthe center of gravity; whereby afiy increase in the propelling thrust will tendto shift the centers of lift and resistance forward to maintain a. balance of forces during acceleration, and whereby the bottom of the hull in rear of the step will skim the surface of the water when at speed.

5. A boat of the character specified com-' prising a hull so designed that its center of gravity is disposed in rear of the mid-section of the hull, the center of resistance being disposed below the center of gravity and forward of the mid-section of the hull, and the center of. lift'disposedforward. of the center of resistance; and means'above the center of gravity for propelling the boat, the center of thrust thereof being disposed above and in rear of the center of gravity; whereby the thrust and resistance forces will tend to revolve the hull around the center will tend to revolve the hull in the opposite direction around the center of resistance in order to maintain a balance of forces during acceleration, and whereby the, rear portion of the hull will skim the surface of the water when at s eed. i

6. A boat of e character specified comprising a hull having a stepped reaction surface; said hull'being sqdesigned that its center of gravity is disposed in rear of the mid-section of the hull5 and the center of resistance being disposed below the center of gravity and forward of the mid-section of the hull, and the center of lift disposedforward of the center of resistance; and an aerial propeller at the'rear of the hull for propelling the boat, the center of thrust thereof being disposed above and in rear of 'the center of gravity; whereby the thrust and resistance forces will tend to revolve the hull in one direction around the center 1 of gravity, and the gravity and lift forceswill tend to revolve the hull in the opposite direction around the center of resistance in order to maintain a balance of forces during acceleration, and whereby the bottom of the HENRY LOWE BRowNBAo 

